Various gearing arrangements have been proposed that increase the output torque of the driven component of a system in relation to the input torque by control of the input-to-output gear ratio.
U.S. Pat. Nos. 2,122,330; 3,156,136; and 4,321,842 disclose rotary drive gear systems in which an internal rotary carrier is arranged with a stationary case and carries a driven gear set that interacts with a stationary sun gear to rotate the carrier and an output shaft with increased torque. In one embodiment of the '842 patent, the carrier mounts an electric motor having a drive shaft on which two cog wheels are mounted that are coupled by endless belts to a pair of sun cogs, one of which is fixed to the external case and the other which is fixed to an output shaft journaling the carrier.
It is an object of the present invention to provide such an electric driven rotary gearing arrangement but of a much simpler design involving fewer parts and improved versatility.